The PR.XIX was the last unarmed reconnaissance variant of the well-known Supermarine Spitfire. Totally 225 were built. Fifty of these were bought, nearly new and in excellent condition,  from the RAF in 1948. They were all provided  to the Reconnaissance Wing F 11 at Nyköping Their Swedish designation became S 31. The aircraft were delivered complete with camera installations and spares. 

The S 31 carried three cameras. One oblique camera type SKa 12 was always fitted. The other two were either two telephoto cameras type SKa 10 or one SKa 10 and one SKa 12.

The Ska10 could be fitted with lenses of 50 cm alt. 92 cm focal length. Most missions were therefore flown  at an altitude of 5.000 alt. 9.200 metres, giving the photographic film a scale of 1/10.000 metres.  

Earlier PR missions used to contain a moment when the aircraft took a main series of photographs while flying right above the target. The S 31 with its side camera was safer as earlier Swedish P.R. aircraft, as the initial oblique photos could be taken from a safe distance of a well-defended target.  

The S 31 was fitted with a Rolls-Royce Griffon 12-cylinder liquid-cooled 66 engine developing 2.055 hp. The aircraft had a pressurized cockpit.  

The Chief of the Swedish Air Force 1942-1954, General Bengt Nordenskiöld, ordered that the Air Force only should look forward. No photos from old times should be saved. Aircraft which have served its time should be sold or scrapped. Fortunately, a few colonels took care of old aircraft from their Wings in spite of the order. But all S 31s were scrapped. The Spitfire on the photo has served in Germany and India, returned to Britain and later sold to Canada. After a lot of difficulties, it was brought to Sweden in bad shape, but after an extensive work, it has been rebuilt to full S31 standard. It was committed to the Flygvapenmuseum (the Swedish Air Force Museum) in 1989. The original Spitfire was once RAF PM627 (C/n 6S-699626) and carries now the fictive RSwAf Number 31051. See photos at top and bottom.  

Photo below: # 31030 visting Kalmar.

Length 9,96 m. Span 11,23 m. MTOW 3.400 kg. Max. Speed 735 km/h.